Connect to the PC, go through the upgrade, registration, etc. After it's all done, don't eject your Glo. Close the Kobo desktop application, locate the drive for your Glo's internal storage, open the .kobo directory and delete the KoboRoot.tgz, manifest.md5sum and the upgrade directory found in it. Then eject your Glo.

After this just avoid upgrading -- no WiFi, delete the files again next time you connect to your PC, etc. There was a hack editing a file that kept a Kobo from upgrading but that does not work anymore. Also a mention of setting the firmware version in the sqlite database to prevent upgrading. I'm not sure if that still works either. It might be worth searching this forum for that information.

Regards,
David

Thankyou David , im using a translator because my english isnt good enoguht but so your telling me that, this downgrade of kobo glo there was a hack that kept kobo from updating but not works anymore and setting the firmware to prevent upgrade , but so i can put the 2.4.0 with that steps that you told me? , the problem is if i understand , that if i conect the glo to wifi this auto upgrade, but so if i dont conect wifi there was no problem? is that right? ;D thank you , and also anybody know if there was a link in this forum about this ? thx